Useful Papers
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Myopia Management
Efficacy in Myopia Control—The Impact of Rebound
Bullimore & Brennan
A study explored whether the increase in myopia typically expected after discontinuing myopia control treatment leads to an expected age- and race-related progression or to an accelerated rebound effect. A PubMed search identified 19 prospective studies with 24 treatment groups, including control and cross-over designs. Annualized rebound was calculated using axial length and myopia progression data. The results showed a mean rebound of +0.05 ± 0.10 mm in axial length and −0.09 ± 0.24D in myopia progression, with rebound severity being significantly correlated with to the treatment’s 1-year efficacy. Optical corrections showed minimal rebound (−0.01 ± 0.03 mm), while the highest rebound was found with red light therapy and atropine use (≥0.14 mm), with overnight orthokeratology rebound ranging from +0.03 to +0.14 mm. The study found no evidence of rebound with myopia control spectacles or soft contact lenses, suggesting future research should examine how age and treatment efficacy influence rebound after treatment cessation.
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Keratoconus Management
Artificial Intelligence versus Conventional Methods for RGP Lens Fitting in Keratoconus
Abadou et al.
This study compared three artificial intelligence (AI) frameworks—Standard Machine Learning (ML), Multi-Layer Perceptron (MLP), and Convolutional Neural Networks (CNN)—against the traditional mean radius of curvature (K) method for predicting the posterior radius of curvature of rigid contact lenses in keratoconus patients. Data from 197 keratoconus eyes fitted with Rose K2® lenses were analyzed using corneal topographic indices and reconstructed maps. While the conventional method achieved an r² of 0.36, AI models significantly outperformed it, with the best results from the EfficientNetB0 CNN trained on topographic maps (r² = 0.80). These findings highlight the superior predictive power of AI, particularly CNNs, for optimizing contact lens fitting in keratoconus management.
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Contact Lens Compliance
Attitudes and Behaviors Regarding Compliance with Contact Lens Wear and Care Among Contact Lens Users at a University Hospital in Turkey
Oruz et al.
This study assessed contact lens (CL) care compliance across different age and occupation groups among 205 CL wearers followed between 2016 and 2022. Participants were classified into good (41.5%), average (35.1%), and poor (23.4%) compliance groups. The most frequent noncompliant behavior was missing aftercare visits. Younger wearers (≤25 years) were more likely to skip hand washing and engage in water activities while wearing CLs, whereas health care workers were significantly more noncompliant regarding exceeding lens replacement times and sleeping with lenses. Additionally, users wearing CLs six to seven days per week had lower compliance. These findings suggest that younger patients, health care workers, and frequent CL users require targeted interventions to improve compliance.
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Contact Lens Practice
International trends in rigid contact lens prescribing (2000-2023): An update
Efron et al.
This study analyzed trends in rigid contact lens prescribing across 20 countries from 2000 to 2023, based on data gathered from eye care practitioners through annual surveys. The results revealed a biphasic pattern, with rigid lens fittings showing a decline from 14.2% of all contact lens fittings in 2000 to 8.1% in 2012, followed by a consistent rise, reaching 16.5% by 2021. The Netherlands (45%) and Hungary (43%) reported the highest prescribing rates, while Greece and Lithuania had the lowest (<1%). The resurgence in rigid contact lens prescribing was reported to be primarily due to their ‘repurposing’ for specialized applications such as scleral/corneo-scleral lenses and orthokeratology, rather than traditional spherical corneal lenses.
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Contact Lens Compliance
Complications and compliance in professionally-managed and self-managed contact lenses compared with non-contact lens wearers
Gantz et al.
A study compared subjective symptoms and ocular complications of soft contact lens (CL) users who did not seek professional follow-up care (self-managed, SM) versus those who were prescribed CLs and their care professionally managed in optometry practices (PM) and to those of a control group of non-CL wearers. The SM, PM, and non-CL wearers cohorts included 127 (mean age: 24.3±5.1, range: 16-45 years, 104 female), 132 (mean age: 25.5±6.2, range: 18-43 years, 103 female), and 56 (mean age: 22.3±3.5, range: 18-39 years, 36 female) participants, respectively. Meibomian gland dysfunction grade, limbal redness, corneal neovascularization, and papillary conjunctivitis were significantly worse in SM CL wearers compared with both the non-CL wearers and PM CL wearers, respectively. Conjunctival staining was significantly worse in the SM cohort compared with the PM cohort. 38.6% of the SM compared with 22.8% of the PM CL wearers, had an inappropriate refractive correction. SM CL wearers wore CLs significantly more years, for more daily hours, and tended to nap or sleep with their CLs compared with the PM CL wearers. The cohorts did not differ in their subjective symptoms. This study highlights that ocular complications are significantly more prevalent in SM CL wearers compared with PM CL wearers, and SM CL wearers tend to wear CLs with incorrect powers, and are less compliant with napping or sleeping with the CLs compared with PM CL wearers, thus emphasizing the importance of fitting, patient education and follow-ups in CL wearers by qualified eye care professionals.
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Contact Lens Care
Microbial contamination in contact lenses, lens care solutions, and accessories among asymptomatic soft contact lens users
Kirkliauskienė et al.
A study evaluated microbial contamination of contact lenses (CL) and their accessories among asymptomatic lens users and identified behavioral risk factors that might exacerbate such contamination. Ninety-five asymptomatic soft CL users participated in the study from whom 380 samples were collected from the inner surface of lenses, the base of lens cases, the tip of the multipurpose solution bottle, and the solution itself. Microscopic examination, culture-based methods, and biochemical tests were used to identify isolated microorganisms. A self-administered questionnaire on compliance with care and hygiene procedures was completed by each participant. The overall microbial contamination of tested samples was 38.7%. The most frequently contaminated items were lens cases (59, 62.1%), followed by bottles (44, 46.3%) and lenses (35, 36.8%). Meanwhile, the lowest incidence of contamination was seen in lens multipurpose solutions (9, 9.5%). The predominant microorganisms recovered were Coagulase-negative Staphylococci (94, 64%) and Gram-positive rods (29, 19.7%). Other identified potential pathogens were Staphylococcus aureus (11, 7.5%), Pseudomonas aeruginosa (5, 3.4%), Escherichia coli (1, 0.7%), and Candida albicans (2, 1.4%). The questionnaire revealed that contact lens users aged 18 to 20 years showed a lack of compliance with proper hygienic care for contact lens maintenance. Risk factors such as male gender, smoking, showering, or swimming while wearing CL were related to microbiological contamination in at least one of the samples. In summary, this study found that the highest degree of contamination was found in lens cases as a result of insufficient lens care practices among study participants. Such noncompliance with the lens cleaning procedures can lead to microbial colonization of the lens and its accessories, thus increasing the risk of ocular complications.
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Keratoconus
Association between family history and the corneal characteristics of keratoconus in Japan
Itoi & Itoi
A retrospective study was conducted in Japan to determine the association between family history and corneal characteristics of keratoconus. Corneal indices derived from anterior segment optical coherence tomography were compared between eyes from patients with positive (2579 eyes) and negative (122 eyes) family history of keratoconus. The study found no significant association between family history and corneal indices in Japanese patients with keratoconus, except for paracentral and mid-peripheral corneal thicknesses. A Japanese patient with keratoconus who had a family history showed significantly lower paracentral and mid-peripheral corneal thicknesses than those with no family history.
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Myopia Management
Light exposure therapy for myopia control: a systematic review and Bayesian network meta-analysis
Zaabaar et al.
A systematic review and meta-analysis compared the myopia control effects in myopic children of different light wavelengths, including red, violet, or full-spectrum light, with the primary study outcomes being axial length elongation and progression of spherical equivalent refraction. Analyses were conducted for all the included clinical studies (12 studies) and separately for only randomised controlled trials (8 studies). When all clinical studies were included (12 studies), only red-light was found to slow both the axial elongation of the eye by -0.38 mm per year and the spherical equivalent refraction progression by 0.72D per year compared with controls, and red light remained the only significant intervention when analyzing randomised controlled trials only (-0.28 mm and 0.57D per year for axial length and spherical equivalent refraction, respectively).
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Contact Lens Discomfort
End-of-day assessment of asymptomatic versus highly symptomatic soft contact lens wearers
Maldonado-Codina et al.
In a prospective study, five key clinical parameters were compared in asymptomatic (N=25) versus highly symptomatic (N=17) contact lens wearers who wore the same soft lens type (i.e., nelfilcon A lenses) over 14 h (reflecting real-world, typical daily lens use).
Upper eyelid margin staining (‘lid wiper epitheliopathy’) was greater and lower eyelid tear meniscus height was decreased in symptomatic compared to asymptomatic patients. Better contact lens comfort scores were associated with lower levels of eyelid margin staining and reduced blink rate. This study highlights the importance of evaluating the ocular surface and tear film during periods of contact lens discomfort.
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Contact Lens Care
Bacterial contamination of multi-use tear drops, gels, and ointments
Yilmaz et al.
A prospective study investigated the bacterial contamination of 271 containers of multi-use teardrops, gels and ointments used by 168 patients at home. The overall bacterial contamination for all containers was relatively low overall (12.2%), but with differences in contamination rates among container types (7.9% for tear drops, 11.7% for gels, and 32% for ointments). Thus, the likelihood of bacterial contamination was affected by container type, being higher in gels and ointments than in drops. Also, the contamination rate was found to be increased in collapsible tube. The authors concluded that although the use of ocular lubricants is safe, patients must be cautious when using multi-use teardrops, gels, and ointments to avoid contamination. Whenever possible, bottles should be preferred instead of collapsible tubes.
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Keratoconus
Central and peripheral corneal sagittal height in keratoconus and healthy eyes
Larrosa et al.
A study compared central and peripheral corneal sagittal height (z) values between 40 eyes from patients with central or paracentral keratoconus (32.0 ± 12.5 years) and 40 eyes from healthy subjects (29.1 ± 7.9 years). The z values, which were referenced to a plane tangent to the corneal apex, were calculated for five circles concentric to the center of the pupil (i.e., 4, 6-, 8-, 9- and 10.5-mm diameters). Keratoconus apex was mainly located at the inferior-temporal corneal quadrant, at a distance from 0.083 mm to 3.59 mm with regards to pupil center. Mean z was larger in keratoconus than in healthy eyes in all corneal diameters. Variation in z values was larger in keratoconus than healthy eyes only at the central cornea (4 mm), but not in the corneal periphery (8, 9 and 10.5 mm). In keratoconus, the frequency of minimum z values in the inferior-temporal quadrant was greater than in healthy eyes. The authors concluded that although peripheral z values were larger in keratoconus, rotational variations were comparable between keratoconus and healthy eyes, suggesting that large diameter spherical rigid corneal contact lenses may be an alternative to scleral lenses in central and paracentral keratoconus.
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Myopia Management
Assessing the rebound phenomenon in different myopia control treatments: A systematic review
Sánchez-Tena et al.
A systematic review of 11 studies randomized controlled studies or post-hoc analyses of randomized controlled studies assessed the rebound effect of myopia control treatments, including spectacles with highly aspherical lenslets or defocus incorporated multiple segments technology, soft multifocal contact lenses, orthokeratology lenses, atropine and low-level light therapy. Unifying the rebound effects of all myopia control treatments, the mean rebound effect for axial length and spherical equivalent refraction were 0.10 ± 0.07 mm [-0.02 to 0.22] and -0.27 ± 0.2 D [-0.71 to -0.03] after 10.2 ± 7.4 months of washout, respectively. Optical treatments showed lower rebound effects compared with atropine and low-level light therapy, with a mean rebound effect for axial length and spherical equivalent refraction of 0.04 ± 0.04 mm [0 to 0.08] and -0.13 ± 0.07 D [-0.05 to -0.2], respectively. The authors concluded that although all treatments for myopia control appear to produce a rebound effect after their cessation, optical treatments induce lower rebound effects than pharmacological or light therapies.
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Contact Lens Care
Biocidal Efficacies of Contact Lens Disinfecting Solutions Against International Organization for Standardization (ISO) Compendial Organisms
Corwin-Buell et al.
A study evaluated and compared the in vitro disinfection efficacies of six commercial lens cleaning and disinfecting products for planned replacement soft contact lenses, including five multi-purpose solutions (MPSs) and one hydrogen peroxide solution (HPS) that acted as control in the presence of organic soil according to the International Organization for Standardization (ISO) ISO 14729 stand-alone test protocol. The five specified compendial organisms, three bacteria (Staphylococcus aureus, Pseudomonas aeruginosa, and Serratia marcescens) and two fungi (Candida albicans and Fusarium solani) were incubated with each solution under standard conditions, after which microbes were recovered and quantified. Each of the solutions evaluated met or exceeded the standard's primary criteria (3-log reduction of bacteria and 1-log reduction of fungi) after incubation for the manufacturer-recommended soaking time, except for COMPLETE MPS, which achieved only 0.4 ± 0.1 average log reduction for C. albicans. However, differences in efficacy between the solutions were noted. This study concluded that care solutions marketed for planned replacement soft CL disinfection generally meet the ISO 14729 standard's primary criteria for reducing populations of compendial organisms, with larger differences between solutions noted with C. albicans.
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Keratoconus
Tear Fluid Inflammatory Proteome Analysis Highlights Similarities Between Keratoconus and Allergic Conjunctivitis
Gijs et al.
Although keratoconus (KC) is conventionally defined as a noninflammatory condition, recent studies have associated keratoconus with allergic conjunctivitis (AC) based on clinical parameters. A study aimed to consolidate this association by performing a proteomic analysis of tear fluid from patients with keratoconus and/or allergic conjunctivitis. Amongst 51 participants, proteomic analysis of tear film were performed in patients with keratoconus (n = 17), allergic conjunctivitis (n =17), or both (n = 17). These results showed that while keratoconus and allergic conjunctivitis are separate conditions, the proteomic profiles indicate a similarity in the underlying mechanisms. Thus, this study confirms the association between KC and AC on a molecular level and raise the importance of redefining KC as an inflammatory condition.
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Myopia Control
Topical Atropine for Childhood Myopia Control - The Atropine Treatment Long-Term Assessment Study
Li et al.
A study reported the long-term safety and outcomes of topical atropine for childhood myopia control. This prospective, double-masked observational study of the Atropine for the Treatment of Myopia (ATOM) 1 and ATOM2 randomized clinical trials took place at 2 single centers and included adults reviewed in 2021 through 2022 from the ATOM1 study (atropine 1% vs placebo; 1999 through 2003) and the ATOM2 study (atropine 0.01% vs 0.1% vs 0.5%; 2006 through 2012). Among the original 400 participants in each original cohort, the study evaluated 71 of 400 ATOM1 adult participants (17.8%) and 158 of 400 ATOM2 adult participants (39.5%). The baseline characteristics (spherical equivalent refractive error and axial lengths from the latter two groups were representative of the original cohort. Among approximately one-quarter of the original participants, use of short-term topical atropine eye drops ranging from 0.01% to 1.0% for a duration of 2 to 4 years during childhood was not associated with differences in final refractive errors and axial length 10 to 20 years after treatment. There was no increased incidence of treatment or myopia-related ocular complications in the 1% atropine-treated group vs the placebo group. These findings may affect the design of future clinical trials, as further studies are required to investigate the duration and concentration of atropine for childhood myopia control.
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Lens handling
Current approaches to soft contact lens handling training - Global perspectives
Vianya-Estopa et al.
An online survey-based, multinational study, which included over 500 responses from contact lens practitioners, examined current approaches to soft contact lens application and removal. Responses were obtained from 31 countries, although almost 50% of them came from UK practitioners. Most respondents reported that the most common approach taught for lens application was holding the upper eyelid by the eyelashes 84.7%) and to hold the lower eyelid with the same hand as the lens (89.4%), with lenses being reported to be applied directly to the cornea by more than half of the respondents (57.7%). The most common approach taught for lens removal was dragging the lens inferiorly from the cornea prior to removal (49.3%) followed by dragging the lens temporally before pinching it off the conjunctiva (27.2%), and directly pinching the lens from the cornea (21.2%). Overall, this study found that various methods are adopted globally for training of application and removal of soft contact lenses, with many advising a patient-specific approach is required for success.
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Specialty Lenses
Keratoconus Management in the Community: A Survey of Optometrists
Angelo et al.
An anonymous survey was disseminated among Optometrists in New Zealand to investigate the patterns of practice and referral criteria used for keratoconus to better understand how the condition is being diagnosed and managed. Responses were received from 168 optometrists (representing 20.0% of the optometrist population). Half (48%) of optometrists had ≥15 years of experience, and 22% prescribed soft contact lenses daily, whereas only 6.4% prescribed rigid gas-permeable (RGP) lenses daily. The main barriers to prescribing RGPs were experience with fitting, low market demand, and patient discomfort. When referring to an ophthalmologist, 41% reported referring on progression of corneal parameters, 27% on initial diagnosis, 21% at no set time, and 10% with a reduction in visual acuity. Most optometrists (64%) would refer for possible surgery when visual acuity dropped between 6/9 and 6/12. Optometrists with greater experience were more likely to prescribe RGP lenses and co-manage patients with ophthalmologists. Ownership of a corneal imaging unit suggested an increased likelihood of prescribing RGP lenses but did not alter referral patterns. The results of this survey indicate that there was a significant discrepancy among New Zealand optometrists in keratoconus management, regarding optical correction modality and referral criteria for ophthalmology review.
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Myopia Control
Comparison of 0.02% atropine eye drops, peripheral myopia defocus design spectacle lenses, and orthokeratology for myopia control
Wang et al.
A study aimed to compare the efficacy of 0.02% atropine, peripheral myopic defocus design spectacle lenses (PMDSL), and orthokeratology (OK) to control axial length (AL) elongation in children with myopia. The comparison analysis was based on a previous cohort study (0.02% atropine group) and retrospective data (PMDSL and OK group). Overall, 387 children aged 6-14 years with myopia - 1.00D to - 6.00D in the three groups were divided into four subgroups according to age and spherical equivalent refraction (SER). The mean axial elongation was 0.30 ± 0.21 mm, 0.23 ± 0.16 mm, and 0.17 ± 0.19 mm in the 0.02% atropine, PMDSL, and OK groups, respectively. Multivariate linear regression analyses showed significant differences in axial elongation among the three groups, especially in children aged 6-10, but not in children aged 10.1-14; the corresponding axial elongation was 0.35 ± 0.21 mm, 0.23 ± 0.17 mm, and 0.21 ± 0.20 mm (P < 0.05 between any two groups, except between PMDSL and OK groups at P > 0.05) and 0.22 ± 0.20 mm, 0.21 ± 0.13 mm, and 0.13 ± 0.18 mm (P < 0.05 between any two groups, except between 0.02% atropine and PMDSL groups at P > 0.05) in children with SER from - 1.00D to - 3.00D and from - 3.01D to - 6.00D, respectively. Within the limits of this study design and using only the current brand of PMDSL, the results of this study indicates that OK appears to be the best method, followed by PMDSL and then 0.02% atropine, for controlling AL elongation over one year. However, different effects were found in the various age and SER.
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Myopia Management
SWOT analysis of ortho-K practice in India
Saoji et al.
Orthokeratology (ortho-K) is a well-established method for both correcting refractive error and slowing myopia progression. A study analyzed the strengths, weaknesses, opportunities and threats (SWOT analysis) to gain knowledge as to how to best establish and implement ortho-K practice in India. The SWOT analysis was performed using a prospective questionnaire consisting of five closed ended statements to be responded using a 5-point likert scale. As strengths, the statement that 'ortho-K is an excellent option for myopia control' was agreed by more than 50% of respondents, and 67% of respondents agreed that advanced topographers have made ortho-K lens fitting easier. As weakness, more than 60% of respondents agreed that ortho-K practice involves investment in instrumentation like topographers and trial lenses, and 50% agreed that due to multiple follow up patients may be lost to follow up. As opportunities, the statement that 'pandemic has necessitated the need for optometrists to explore myopia control options such as ortho-K' was agreed by more than 50%. And, as threats, 'reluctance from adults and parents to try overnight contact lenses for myopia correction/control' was agreed by more than 50% of respondents, and 62% agreed that atropine is perceived as an effective myopia control option by majority of the Indian ophthalmologists. In conclusion, this study identified ortho-K as an emerging modality for myopia management in India and informs practitioners and the contact lens industry how to approach ortho-K appropriately.
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Contact Lens Lifestyle
TFOS Lifestyle: Impact of contact lenses on the ocular surface
Jones et al.
A recent systematic review and meta-analysis identified that the influence of lifestyle factors on soft contact lens dropout remains poorly understood, and is an area in need of further research. Overall, this review investigated lifestyle-related choices made by clinicians and contact lens wearers and discovered that when appropriate lifestyle choices are made, contact lens wear can enhance the quality of life of wearers.
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Specialty Lenses
Therapeutic applications of contact lens-based drug delivery systems in ophthalmic diseases
Zhao et al.
Traditional ophthalmic drugs, such as eye drops, gels and ointments, are accompanied by many problems, including low bioavailability and potential drug side effects. Innovative ophthalmic drug delivery systems have been proposed to overcome the limitations associated with traditional formulations. This review discusses the latest developments in drug-loaded contact lenses for the treatment of ophthalmic diseases, including preparation methods, application in ophthalmic diseases and future prospects.
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Myopia Control
Efficacy of Repeated Low-Level Red-Light Therapy for Slowing the Progression of Childhood Myopia: A Systematic Review and Meta-analysis
Tang et al.
A recent systematic review and meta-analysis evaluated the long-term efficacy and safety of repeated low-intensity red light (RLRL) treatment for childhood myopia. This analysis included 13 studies (8 randomized controlled trials, 3 non-randomized controlled trials, and 2 cohort studies) involving 1857 children and adolescents. Eight studies met the meta-analysis criteria, and the weighted mean difference (WMD) for myopia progression between RLRL and the control group was 0.68 diopters (D) per 6 months (95% CI = 0.38 to 0.97 D; I2 = 97.7%; P < .001) for spherical equivalent refractive error change; -0.35 mm per 6 months (95% CI = -0.51 to -0.19 mm; I2 = 98.0%; P < .001) for axial elongation; and 36.04 µm per 6 months (95% CI = 19.61 to 52.48 µm; I2 = 89.6%; P < .001) for subfoveal choroid thickness change. The study concluded that RLRL therapy may be effective for delaying the progression of myopia. However, the evidence found is low certainty, and larger and better randomized clinical trials with 2-year follow-ups are needed to improve the existing state of knowledge to inform medical guidelines more comprehensively.
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Myopia Management
IMI-Global Trends in Myopia Management Attitudes and Strategies in Clinical Practice-2022 Update
Wolffsohn et al.
Surveys in 2015 and 2019 identified a high level of eye care practitioner concern/activity about myopia, but the majority still prescribed single vision interventions to young myopes. A self-administered, internet-based questionnaire was distributed in 2022 in 13 languages, through professional bodies to eye care practitioners globally to provide updated information. Of the 3195 respondents, practitioners' concern about the increasing frequency of pediatric myopia in their practices differed between continents (P < 0.001), being significantly higher in Asia (9.0 ± 1.5 of 10) than other continents (range 7.7-8.2; P ≤ 0.001). Overall, combination therapy was perceived by practitioners to be the most effective method of myopia control, followed by orthokeratology and pharmaceutical approaches. The least effective perceived methods were single vision distance undercorrection, spectacles and contact lenses, as well as bifocal spectacles. Practitioners rated their activity in myopia control between (6.6 ± 2.9 in South America to 7.9 ± 1.2/2.2 in Australasia and Asia). Single-vision spectacles are still the most prescribed option for progressing young myopia (32.2%), but this has decreased since 2019, and myopia control spectacles (15.2%), myopia control contact lenses (8.7%) and combination therapy (4.0%) are growing in popularity. The study concluded that more practitioners across the globe are practicing myopia control, but there are still significant differences between and within continents. Practitioners reported that embracing myopia control enhanced patient loyalty, increasing practice revenue and improving job satisfaction.
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Contact Lens Safety
Incidence of Corneal Adverse Events in Children Wearing Soft Contact Lenses
Bullimore & Richdale
There is increasing interest in fitting children with soft contact lenses, partly due to the increase in prescribing of designs to slow the progression of myopia. A literature review summarized large prospective and retrospective studies that include data on the incidence of microbial keratitis and corneal infiltrative events (CIEs) in children wearing soft contact lenses. Seven prospective studies published between 2004 and 2022 were identified representing 3,752 patient years of wear in 1,756 children, nearly all of whom were fitted at age 12 years or younger. Collectively, they report one case of microbial keratitis and 53 CIEs, of which 16 were classified as symptomatic. The overall incidence of microbial keratitis was 2.7 per 10,000 patient years (95% confidence intervals [CI]: 0.5-15), and the incidence of symptomatic CIEs was 42 per 10,000 patient years (95% CI: 26-69). Two retrospective studies were identified representing 2,545 patient years of wear in 1,025 children, fitted at age 12 years or younger. One study reports two cases of microbial keratitis giving an incidence of 9.4 per 10,000 patient years (95% CI: 0.5-15). Overall, the results of this literature review indicates that the incidence of microbial keratitis in children wearing soft lenses is no higher than in adults, and the incidence of CIEs seems to be markedly lower.
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Specialty Lenses
Clinical Outcomes of a Randomized Trial with Contact Lenses for Astigmatic Myopia Management
Tomiyama & Richdale
There are limited treatment options for myopia management of patients with moderate to high astigmatism. Thus, a study quantified objective and subjective clinical differences between toric orthokeratology and soft toric multifocal contact lenses in the same cohort, which included 30 adult subjects with refractive myopia (plano to -5.00 D) and moderate to high astigmatism (1.25 to 3.50 D). Participants wore lenses for 10 days in random order, separated by a 14-day washout period. High-contrast visual acuity, low-contrast visual acuity, and glare logMAR visual acuity were measured. Surveys ascertained subject preference for comfort, vision, handling, and cost. A subset of participants (n = 17) who achieved good vision with both lens types was analyzed. High-contrast and glare acuity with toric orthokeratology were reduced by one line compared with soft toric multifocal lenses (both 0.00 vs. -0.10, p ≤ 0.003). Participants preferred toric orthokeratology for vision (p ≤ 0.03) but soft toric multifocal lenses for handling (p ≤ 0.006). When forced to choose between lens types, participants preferred toric orthokeratology for vision and overall (both p ≤ 0.007). Overall, these results indicate that although toric orthokeratology caused reduced visual acuity, it was preferred subjectively for vision and overall in comparison with soft toric multifocal contact lenses.
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Myopia Control
Efficacy in Myopia Control: Does Race Matter?
Bullimore & Brennan
The range of available myopia control modalities is increasing rapidly together with the number of studies assessing the efficacy of these treatment options. These are typically evaluated in single-center studies with limited racial diversity. A recent study evaluated the extent to which results on one race can be extrapolated to others; more specifically, whether results from studies conducted on East Asian children can be applied to Western children and vice versa. Two multicenter, randomized clinical trials that assessed two different myopia control soft contact lenses failed to show that race had a significant effect on the slowing of myopia progression. Although multicountry trials are rare, there are three myopia control modalities that have been evaluated in different populations albeit in different clinical trials: progressive addition lenses, overnight orthokeratology, and 0.01% atropine. Studies conducted with progressive addition spectacles lenses, overnight orthokeratology contact lenses and atropine eye drops revealed remarkably similar slowing of axial elongation and myopia progression between East Asian and Western children indicating that, based on the available evidence, the efficacy of individual myopia control treatments is largely independent of race.
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Compliance
Lens Care Compliance Rates and Perceptions Among Rigid Gas Permeable Contact Lens Wearers - A Pilot Study
Kutija et al.
A study was conducted to estimate compliance rate among rigid gas permeable lens wearers (RGPLW) using a lens care system, identify procedures in lens care process with the poorest compliance levels, and assess concordance between participant reported practices and their subjectively perceived compliance. Fifty contact lens wearers (mean age 34.6 years, 68% female) filled out a questionnaire that included demographic data, duration of lens wear, self-evaluation compliance grade, and 14 lens care procedures and wearing habits indicative of compliance. Among all these, full compliance was found in one single patient. The mean number of non-compliant procedures was 5.48, with 32% of participants being non-compliant in more than 50% of the compliance criteria. Critical procedures of the lens care process were infrequent lens case exchange (74%), using tap water for lens care (70%), and improper case cleaning (68%). The mean lens case replacement time was 9.8 months (SD 6.76), with only 26% of patients replacing lens case at least once in 3 months. Excessive daily lens wear was associated with greater total number of non-compliant procedures (p<0.0008). RGPLW were aware of their inappropriate lens care only when achieved non-compliance in almost 50% of the procedures. In conclusion, this study found that RGPLW were not aware of their extremely low compliance rate in several aspects of lens and lens case maintenance.
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Myopia Control
Reduction of Myopic Progression Using a Multifocal Soft Contact Lens: A Retrospective Cohort Study
Cooper et al.
A study evaluated myopia progression over an approximately 6-year follow-up period in children and young adults wearing a commercially available, daily disposable, soft multifocal contact lens with an extended depth of focus (center distance) design. This retrospective cohort analysis included data from 196 patients of mean (SD) age 12.3 (2.7) years (range, 5-20 years), fit with the NaturalVue Multifocal (NVMF) contact lens at 15 practices in the United States over 6 years. All patients showed at least -0.50D of myopic progression in at least one eye prior to wearing the lens. After wearing these lenses for 6-72 months, the average myopia progression slowed by approximately 0.84 D or 85% compared to baseline, which was statistically significant at all time points (P < 0.0001). Frequency distribution revealed that 91% of wearers showed a decrease in myopia progression compared to baseline, with 79% of wearers showing a ≥70% reduction in myopia progression. The average change in axial length in a subset of the population over 47 months of follow-up was approximately 0.10 mm/year. Compared with changes expected in an age- and ethnicity-matched myopic virtual control group obtained from published meta-analysis data, both myopic refractive error progression and axial elongation were significantly lower in NVMF wearers at 12, 24 and 36 months (P < 0.001). Analysis of the age- and ethnicity-matched virtual control group predicted that the Cumulative Absolute Reduction of axial Elongation (CARE) value over 3 years would be 0.45 mm. Based on these results, this study concluded that wearers of the soft multifocal contact lens displayed significant reductions in myopia progression throughout a follow-up period of 6 years.
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Specialty Lenses
Orthokeratology lenses with increased compression factor (OKIC): A 2-year longitudinal clinical trial for myopia control
Lau et al.
A study investigated the effectiveness of orthokeratology (ortho-k) lenses and corneal changes with increased compression factor for myopia control over a 2-year period. Young participants (age: 6-<12 years), with low myopia (0.50-4.00 D) and low astigmatism (≤1.25 D), were recruited and allowed to choose to wear either single-vision spectacles or ortho-k lenses (randomly assigned to compression factor of either 0.75 or 1.75 D). Axial length and cycloplegic refraction were measured at six monthly intervals for two years by a masked examiner. A significant number of control (63 %) dropped out, mainly due to concern about myopia progression (58 %). A total of 75 participants (mean age: 9.3 ± 1.0 years; control: n = 11, ortho-k [0.75 D]: n = 29, ortho-k [1.75 D]: n = 35) completed the study. Considering ortho-k groups only, the mean axial elongation of participants wearing ortho-k lenses of conventional compression factor (0.75 D) and increased compression factor (1.75 D) were 0.53 ± 0.29 and 0.35 ± 0.29 mm, respectively, over the 2-year study period. The between-group differences in corneal health were not significant at all visits. The authors concluded that participants wearing ortho-k lenses of increased compression factor further slowed axial elongation by 34%, when compared with the conventional compression factor without compromising corneal health, but further investigations are warranted to confirm the potential mechanism of an increased compression factor for improved myopia control effectiveness.
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Contact Lens Care
Antimicrobial Efficacy of an Ultraviolet-C Device against Microorganisms Related to Contact Lens Adverse Events
Dumpati et al.
A study assessed the antimicrobial activity of an ultraviolet-C (UVC) device, with an emitting 4.5 mm diameter Light Emitting Diode (LED; 265 nm; 1.93 mJ/cm2), against microorganisms implicated in contact lens related adverse events. Pseudomonas aeruginosa, Staphylococcus aureus, Fusarium solani, and Candida albicans agar plate lawns were exposed to the device beams for 15 and 30 s at 8 mm distance. Following the exposure, the diameter of the growth inhibition zone was recorded. Contact lenses made of Delfilicon-A, Senofilicon-A, Comfilicon-A, Balafilicon-A, Samfilicon-A and Omafilicon-A and a commercially available contact storage case was used. They were exposed to bacterial and fungal strains for 18 h at 37 °C and 25 °C respectively. After this, the samples were exposed to UVC for 30 s at 8 mm distance to determine the antimicrobial efficacy. Samples were then gently washed and plated on appropriate agar for enumeration of colonies. The UVC exposure reduced microbial growth by 100% in agar lawns, and significantly (p < 0.05) reduced microbial contamination to contact lenses and cases, ranging between 0.90 to 4.6 log. In conclusion, this study found that very short UVC exposure has high antimicrobial efficacy against most of the predominant causative microorganisms implicated in contact lens related keratitis, and thus it could be readily used as a broad-spectrum antimicrobial treatment for lens disinfection.
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Compliance
Are Patients Sufficiently Informed about Contact Lens Wear and Care?
Alonso et al.
Frequent and effective patient-practitioner communication is essential to ensure instructions regarding contact lens use, care and maintenance are understood and followed. Given the relevance of good patient compliance, a study was conducted to determine the content and type of information Optometrists provide to patients during the first contact lens fitting and at follow-up visits. A self-reported ad hoc survey was distributed to Optometrists to investigate, amongst other factors, whether practitioners provided information on several aspects of contact lens use and maintenance; how was this information provided; and whether in-office practical demonstrations were conducted at all contact lens appointments. Respondents of 321 surveys had a median of 20 years of contact lens fitting experience and worked on independent practices (67.6%), national (29.0%) and regional chains (3.4%). Type of practice significantly influenced continuous education habits (p = 0.03). Overall, 28.0% of participants did not always instruct patients on the need to rub contact lenses, 34.3% did not always address contact lens replacement and 6.8% did not always explain storage case hygiene and replacement. At the follow-up visit, only 8.4% of respondents asked their patients to demonstrate their care routines. Information was mostly oral (48.6%) or oral and written (43.0%). Contact lens-related complications were reported more frequently by participants with less continuous education training (p = 0.01), by those not always recommending rubbing (p = 0.002) and by those not providing written information about storage case hygiene and replacement (p = 0.002). These results highlight that patient-practitioner communication was good, albeit several areas were identified were information was insufficient or not provided in a correct and timely format. Precise, written information on rubbing and storage case hygiene and replacement may improve compliance and assist in avoiding complications and drop-out.
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Contact Lens Care
The impact of a rub and rinse regimen on removal of human coronaviruses from contemporary contact lens materials
Lourenco Nogueira et al.
A study assessed the influence of contemporary contact lens (CL) materials on human coronavirus attachment and the influence of a rub and rinse step to remove these viruses. Binding rates of HCoV-229E and HCoV-OC43 to eight soft CL materials and four rigid gas permeable materials were analyzed. The impact of a rub and rinse step to remove these viruses from all materials was examined. The efficacy of Biotrue (Bausch & Lomb), OPTI-FREE Puremoist (Alcon), Clear Care (Alcon) and cleadew (Ophtecs) to remove virus contamination from two representative soft lens materials (etafilcon A and lotrafilcon B) was also determined. Approximately 102 to 103 infectious viral particles were recovered from each CL material. Although some materials were more prone to coronavirus adhesion, contamination of both viral types was reduced to below the limit of quantification (LQ) from all materials using a simple saline rinse step. Exposure to Clear Care and cleadew reduced the number of infectious viral particles from both etafilcon A and lotrafilcon B to below the LQ, while for Biotrue and OPTI-FREE Puremoist, infectious viral particles were reduced to below the LQ only when additional rub and rinse steps were included. Overall, this study concluded that human coronavirus contamination can be easily removed from CL surfaces. Although CL care products containing hydrogen peroxide and povidone-iodine efficiently removed virus contamination from CL surfaces without the need for a rub and rinse step, a full regimen including rub and rinse steps is crucial when using CL care products based on non-oxidative systems.
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Specialty Lenses
Contact lens prescribing trends in the UK hospital eye service
Naroo et al.
A study evaluated the types of contact lenses fitted by hospital optometrists within the Midlands region of the United Kingdom (UK). A questionnaire was sent to all the lead optometrists of the Midlands Hospital Optometry Group, which includes optometry hospital eye departments within the Midlands region of the UK. The questionnaire requested information of their last ten contact lens fitting appointments. Details of the patient's age, gender, lens type, wearing times, and presenting condition were retrospectively taken from the patients' records using the appointment diary to identify the last ten patients fitted with contact lenses. Details from a total of 109 contact lens fits were collected. This included 45 females and 64 males with a mean age of 39.4 ± 17.4 years. The mean wearing time was 6.3 ± 1.0 days per week and 10.7 ± 5.1 h per day. Sixty-one percent of the contact lenses fitted were for patients with keratoconus and over half of all the contact lenses fitted were corneal rigid gas permeable lenses. This study highlights that the main reason for fitting contact lenses in hospital contact lens practice is primary corneal ectasia, and mainly keratoconus. Whilst most patients with keratoconus were fitted with corneal rigid gas permeable contact lenses, around 1 in 6 were fitted with soft contact lenses.
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Myopia Control
Combined 0.01% atropine with orthokeratology in childhood myopia control (AOK) study: A 2-year randomized clinical trial
Tan et al.
A study investigated whether combining 0.01% atropine with orthokeratology (AOK) has a better effect in retarding axial elongation compared with orthokeratology alone (OK) over two years. A total of 96 Chinese children aged six to < 11 years with myopia (1.00 - 4.00 D, inclusive) were randomized into either the AOK or OK group in a 1:1 ratio. Axial length (the primary outcome), and secondary outcomes (e.g. pupil size and choroidal thickness) were measured at 1-month and at 6-monthly intervals after commencement of treatment. AOK subjects had statistically slower axial elongation (adjusted mean [standard error], 0.17 [0.03] mm vs 0.34 [0.03] mm, P < 0.001), larger increase in mesopic (0.70 [0.09] mm vs 0.31 [0.09] mm, P = 0.003) and photopic pupil size (0.78 [0.07] mm vs 0.23 [0.07] mm, P < 0.001), and greater thickening of the choroid (22.6 [3.5] µm vs -9.0 [3.5] µm, P < 0.001) than OK subjects over two years. Slower axial elongation was associated with a larger increase in the photopic pupil size and a greater thickening in the choroid in the AOK group.
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Compliance
Compliance behavior change in contact lens wearers: a randomized controlled trial
Arshad et al.
Water exposure during contact lens wear has been associated with contact lens disease including microbial keratitis and sterile corneal infiltrates. Despite documented risks, water exposure is common amongst lens wearers. A study aimed to determine the effect of water education in the form of "no-water" lens case stickers on water-contact behaviors and storage case contamination. In a prospective, masked, randomized controlled trial, 200 daily lens wearers were randomized to either receive a storage case with a "no-water" sticker (test) or without a "no-water" sticker (control). Both groups received written compliance information. Participants completed a self-administered lens hygiene questionnaire at baseline and after 6 weeks. Microbial analysis of used storage cases was conducted to assess overall microbial contamination and endotoxin levels. A total of 188 lens wearers completed both study visits. After 6 weeks, the overall water exposure score and endotoxin levels reduced significantly in the test group compared with the control group (p < 0.05). There were no significant changes in individual water-contact behaviors or overall storage case contamination. A no-water infographic on the contact lens case improved overall water-contact behaviors and reduced storage case endotoxin.
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Contact Lens Practice
Opportunities and threats to contact lens practice: A global survey perspective
Thite et al.
A study aimed to understand the views of contact lens (CL) practitioners across the globe regarding what they perceive as opportunities and threats in CL practice. A self-administered anonymized questionnaire was distributed through international professional bodies and academic institutions worldwide. The questionnaire included items on demographic characteristics, type of practice, and questions designed to explore practitioners' perspective on the future of their CL practice over the next five years. A total of 2408 valid responses were analyzed. Multifocal CLs for presbyopia, CLs for myopia control, use of daily disposable (DD) CLs for occasional wear, and biocompatible materials to improve comfort were identified as promising areas of opportunities by practitioners (all 8/10). Respondents from North America, and Europe valued DDCLs for occasional wear moderately more favorable (median: 9/10 for all) as compared to colleagues in Asia (median: 8/10, p < 0.001), South America (median: 8/10, p < 0.01), and Africa (median: 8/10p < 0.01). Multifocal CLs for presbyopia was perceived as a better opportunity by practitioners in North America and Europe (median: 9/10 for both), as well as in Australasia (median: 8/10), in comparison to Asia, Africa, and Middle East (for all Median: 6/10, p < 0.001). Practitioners expressed concerns about the availability of CLs and CL prescriptions online without direct professional involvement (both 9/10). Overall, the most appealing opportunities for CL practice growth were identified in occasional use of DD CLs, biocompatible materials to reduce CL discomfort, multifocal CLs for presbyopia correction and management of myopia control with CLs. Lack of regulation in CL sales, especially online, seemed to be a constant threat. The insights from this study can be used to design targeted strategies to enhance CL practice across the globe and in specific geographical areas.
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Specialty Lenses
Keratoconus: An updated review
Santodomingo-Rubido et al.
Keratoconus is a bilateral and asymmetric disease which results in progressive thinning and steeping of the cornea leading to irregular astigmatism and decreased visual acuity. Traditionally, the condition has been described as a noninflammatory disease; however, more recently it has been associated with ocular inflammation. Keratoconus normally develops in the second and third decades of life and progresses until the fourth decade. The condition affects all ethnicities and both sexes. The prevalence and incidence rates of keratoconus have been estimated to be between 0.2 and 4,790 per 100,000 persons and 1.5 and 25 cases per 100,000 persons/year, respectively, with highest rates typically occurring in 20- to 30-year-olds and Middle Eastern and Asian ethnicities. Progressive stromal thinning, rupture of the anterior limiting membrane, and subsequent ectasia of the central/paracentral cornea are the most commonly observed histopathological findings. A family history of keratoconus, eye rubbing, eczema, asthma, and allergy are risk factors for developing keratoconus. Detecting keratoconus in its earliest stages remains a challenge. Corneal topography is the primary diagnostic tool for keratoconus detection. In incipient cases, however, the use of a single parameter to diagnose keratoconus is insufficient, and in addition to corneal topography, corneal pachymetry and higher order aberration data are now commonly used. Keratoconus severity and progression may be classified based on morphological features and disease evolution, ocular signs, and index-based systems. Keratoconus treatment varies depending on disease severity and progression. Mild cases are typically treated with spectacles, moderate cases with contact lenses, while severe cases that cannot be managed with scleral contact lenses may require corneal surgery. Mild to moderate cases of progressive keratoconus may also be treated surgically, most commonly with corneal cross-linking. A recent publication provides an updated review on the definition, epidemiology, histopathology, aetiology and pathogenesis, clinical features, detection, classification, and management and treatment strategies for keratoconus.
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Myopia Control
Efficacy and Safety of Different Add Power Soft Contact Lenses on Myopia Progression in Children: A systematic review and meta-analysis
Yu et al.
Soft multifocal contact lenses (SMCLs) are widely used to control myopia progression in children; however, the efficacy and adverse effects to the use of SMCLs of different added powers remains to be explored. A systematic review and meta-analysis evaluated the results from seven independent studies involving 805 children in terms of the weighted mean differences (WMD) in myopic progression, axial length, and odds ratios (ORs) for adverse effects and dropout rates between SMCLs with different added powers and control groups. At 1-year, the WMD in myopia progression between SMCL and control groups was -0.22 diopters (D) (95% CI, -0.56-0.12 D) for low add power SMCLs, 0.09 D (95% CI, 0-0.19 D) for medium add power, and 0.2 D (95% CI. 0.13, 0.27 D) for high add power. At 2-years, the WMD for medium add power was 0.12 D (95% CI, -0.03-0.27 D), and for high add power was 0.25 D (95% CI, 0.14-0.35 D). No differences were detected for adverse effects (p = 0.2) and acceptability (p = 0.74) between different added powers. Additionally, differences in visual performance changes, produced by different added powers, were not detected. The present meta-analysis showed that high add power SMCLs are more effective and stable to control myopia progression, whereas adverse effects and acceptability were not related to the added power.
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Compliance
Compliance vs. Risk Awareness with Contact Lens Storage Case Hygiene and Replacement
Cardona et al.
A study evaluated the level of compliance regarding contact lens (CL) storage case hygiene and replacement, as well as the type of information provided by eye care practitioners regarding lens handling and patients’ risk perception to lens wear compliance. A survey was used to collect demographic and CL wear details, compliance with storage case care, type of received information from practitioners and risk perception (in a 1-to-5 scale). Non-daily disposable wearing participants, with a median age of 24 years (76.9% females), returned 299 completed surveys. Most participants were monthly replacement silicone hydrogel CL wearers who use multipurpose solutions. Self-reported compliance with storage case care was poor, with 19.1% of respondents reporting never cleaning their cases, 68.6% exposing them to tap water, and 26.4% failing to replace them within 6 months of acquisition. Two-thirds of respondents reported receiving specific information on case maintenance from practitioners, mainly in oral form. Perceived risk associated with poor-compliance practices was high (median values of 4 and 5), and increased with educational level (P = .02, regarding hand-washing; P = .03, regarding case hygiene), years of CL wear experience (P < .001, regarding hand-washing) and in those patients provided with specific information on CL case care (P = .01, regarding case replacement). Despite compliance with hygiene and replacement of contact lens storage cases is key to avoid contact lens contamination and anterior ocular surface complications, this study found that compliance with CL storage case hygiene and replacement was generally poor, even in patients with awareness of the risk associated with non-compliance. Strategies must be explored to increase risk awareness through education as this may lead to better compliance practices.
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Orthokeratology
CLEAR – Orthokeratology
Vincent et al et al.
Orthokeratology (ortho-k) is the process of deliberately reshaping the anterior cornea by utilizing specialty contact lenses to temporarily and reversibly reduce refractive error after lens removal. Modern ortho-k utilizes reverse geometry lens designs, made with highly oxygen permeable rigid materials, worn overnight to reshape the anterior cornea and provide temporary correction of refractive error. More recently, ortho-k has been extensively used to slow the progression of myopia in children. A recent report reviewed the practice of ortho-k, including its history, mechanisms of refractive and ocular changes, current use in the correction of myopia, astigmatism, hyperopia, and presbyopia, and standard of care. Suitable candidates for ortho-k are described, along with the fitting process, factors impacting success, and the potential options for using newer lens designs. Ocular changes associated with ortho-k, such as alterations in corneal thickness, development of microcysts, pigmented arcs, and fibrillary lines are reviewed. The safety of ortho-k is extensively reviewed, along with an overview of non-compliant behaviors and appropriate disinfection regimens. Finally, the role of ortho-k in myopia management for children is discussed in terms of efficacy, safety, and potential mechanisms of myopia control, including the impact of factors such as initial fitting age, baseline refractive error, the role of peripheral defocus, higher order aberrations, pupil size, and treatment zone size.
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Specialty Lenses
CLEAR - Scleral lenses
Barnett et al.
Scleral lenses were the first type of contact lens, developed in the late nineteenth century to restore vision and protect the ocular surface. With the advent of rigid corneal lenses in the middle of the twentieth century and soft lenses in the 1970's, the use of scleral lenses diminished; in recent times there has been a resurgence in their use driven by advances in manufacturing and ocular imaging technology. Scleral lenses are often the only viable form of contact lens wear across a range of clinical indications and can potentially delay the need for corneal surgery. This academic report provides a brief historical review of scleral lenses and a detailed account of contemporary scleral lens practice including common indications and recommended terminology. Recent research on ocular surface shape is presented, in addition to a comprehensive account of modern scleral lens fitting and on-eye evaluation. A range of optical and physiological challenges associated with scleral lenses are presented, including options for the clinical management of a range of ocular conditions. Future applications which take advantage of the stability of scleral lenses are also discussed. In summary, this report presents evidence-based recommendations to optimize patient outcomes in modern scleral lens practice.
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Myopia Control
IMI Impact of Myopia
Sankaridurg et al.
Myopia affected nearly 30% of the world population in 2020 and this number is expected to rise to 50% by 2050. As a result of the latter, the global burden of myopia is also growing. A review from the International Myopia Institute analyzed the impact of myopia on individuals and society; summarizing the evidence for recent research on the prevalence of myopia and high myopia, lifetime pathological manifestations of myopia, direct health expenditure, and indirect costs such as lost productivity and reduced quality of life (QOL). As a result of the rising prevalence of myopia and high myopia, with a disproportionately greater increase in the prevalence of high myopia, this review forecasts a future increase in vision loss due to uncorrected myopia as well as high myopia-related complications such as myopic macular degeneration. Also, QOL has been found to affect those with uncorrected myopia, high myopia, or complications of high myopia. Overall the current global cost related to direct health expenditure and lost productivity has been estimated to be in the billions. Health expenditure is greater in adults, reflecting the added costs due to myopia-related complications. Unless the current trajectory for the rising prevalence of myopia and high myopia change, the costs are expected to grow. The past few decades have seen the emergence of several novel approaches to prevent and slow myopia. Further work is needed to understand the life-long impact of myopia on an individual and the cost-effectiveness of the various novel approaches in reducing the burden.
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Compliance
Assessment of patient compliance in orthokeratology and analysis of influencing factors: a cross-sectional study
Bian et al.
Patient non-compliance with orthokeratology contact lens wear has been shown to be a major risk factor for contact lens-associated complications. A study conducted in China aimed to investigate the compliance with wear and care behaviors of 238 orthokeratology patients and analyze its influencing factors through the use a questionnaire. The subjects' ages ranged from 7 to 25 (mean ± SD, 11.3 ± 2.5) years. The compliance with wear and care behaviors was 19.7%, and the subjects' self-assessment compliance was 96.6%. The compliance rate of subjects wearing lenses for less than 1 year was higher than that of subjects wearing lenses for more than 1 year (p < 0.001). In the first year, the compliance rates of wearing experiences for less than 1 month, 1 month, 3 months, 6 months, and more than 6 months were 45, 29, 21.6, 20, and 27.6%, respectively; no statistically significant differences in compliance were found among these periods (p = 0.314). No correlation was identified between compliance and age (r = - 0.061, p = 0.527) or sex (r = 0.114, p = 0. 751). There was no correlation between compliance and lens care operator (r = - 0.626, p = 0.151). Overall, this study concluded that compliance with orthokeratology lens wear was poor in the cohort assessed. After wearing orthokeratology lenses for more than 1 year, compliance with wear and care behaviors declined. As such, the authors recommended that measures should be taken in clinical practice to solve these problems and improve the safety of orthokeratology contact lens wear.
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Myopia Control
Myopia Progression as a Function of Sex, Age, and Ethnicity
Jones-Jordan et al.
A group of researchers in the US aimed to model juvenile-onset myopia progression as a function of race/ethnicity, age, sex, parental history of myopia, and time spent reading or in outdoor/sports activity. The study included 594 children with at least three study visits: one visit with a spherical equivalent (SPHEQ) less myopic/more hyperopic than -0.75 diopter (D), the first visit with a SPHEQ of -0.75 D or more myopia (onset visit), and another after myopia onset. Younger children were found to have faster progression of myopia; for example, the model-estimated 3-year progression in an Asian American child was -1.93 D when onset was at age 7 years compared with -1.43 D when onset was at age 10 years. Annual progression for girls was 0.093 D faster than for boys. Asian American children experienced statistically significantly faster myopia progression compared with Hispanic (estimated 3-year difference of -0.46 D), Black children (-0.88 D), and Native American children (-0.48 D), but with similar progression compared with White children (-0.19 D). Parental history of myopia, time spent reading, and time spent in outdoor/sports activity were not statistically significant factors in multivariate models. In conclusion, younger age, female sex, and racial/ethnic group were the factors associated with faster myopic progression. This model can facilitate the planning of clinical trials for myopia control interventions by informing the prediction of myopia progression rates.
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Specialty Lenses
Optimizing correction of coma aberration in keratoconus with a novel soft contact lens
Susaki et al.
A group of Japanese researchers reported on the development of a second-generation prototype contact lens (modified lens) with enhanced optics to correct coma aberration in patients with keratoconus (KC). The performance of the modified lens was compared with that of a first-generation prototype contact lens (conventional lens) also optimized to correction coma aberration. Both lenses were designed as a set of standardized soft contact lenses (SCLs) with asymmetric powers along the posterior surface. The modified lens differs from the conventional lens in that the optical zone is decentered superiorly by 0.7 mm. Thirty-four KC eyes were included. Both lenses significantly decreased coma aberration compared to no-lens wear, with the reduction in coma aberration being significantly greater with the modified lens than with the conventional lens. No significant differences in manifest refraction or distance visual acuity were found among the three conditions. Quality of vision was significantly better with the modified lens than with no lens wear, but no differences were found between the SCLs. The on-eye optical center position relative to the pupil was closer to the pupil center using the modified lens than the conventional lens. Optimization of the location of the optical zone in a standardized asymmetric soft contact lens improves correction of coma aberrations and on-eye optical centration.
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Orthokeratology
Adjunctive effects of orthokeratology and atropine 0.01% eye drops on slowing the progression of myopia
Zhou et al.
A group of Chinese researchers investigated the adjunctive effects of using both orthokeratology and 0.01% atropine eye drops for controlling the progression of myopia in children aged 8 to 13 years and with spherical equivalent refraction (SER) ranging from -2.00 to -5.00 D. Participants were allocated into a combination group (i.e., orthokeratology and 0.01% atropine) or atropine group (0.01% atropine). Axial length and spherical equivalent refraction were measured at baseline and then every three months post-treatment for two years. Following two years of treatment, the average SER change was 0.88 ± 0.31 D and 1.14 ± 0.63 D in the combination and atropine groups, respectively, with an average increment in axial length of 0.50 ± 0.17 mm and 0.61 ± 0.21 mm, respectively. In conclusion, orthokeratology and 0.01% atropine eye drops combination therapy was found to be more effective in reducing both myopia progression and the axial elongation of the eye than atropine monotherapy.
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Lens Care
Antiviral effect of multipurpose contact lens disinfecting solutions against coronavirus
Yasir et al.
A study evaluated the antiviral potential against coronavirus of five multipurpose disinfecting solutions, including Biotrue, renu Advanced [Bausch and Lomb], ACUVUE RevitaLens [Johnson and Johnson Vision], cleadew [Ophtecs corp.] or AOSept Plus [Alcon]). Solutions were mixed with coronavirus and surviving viruses from each sample were quantified. The three multipurpose disinfecting solutions Biotrue, renu Advanced and ACUVUE RevitaLens did not kill the coronavirus at the manufacturers recommended disinfection time in the stand-alone test. In contrast, AOSept Plus (hydrogen peroxide) and cleadew (povidone iodine) significantly reduced the numbers of coronaviruses to below the detection limit. This study shows that oxidative contact lens disinfecting solutions (i.e. those containing povidone-iodine or hydrogen peroxide) provide superior antiviral activity against a coronavirus.
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Myopia Control
The Risks and Benefits of Myopia Control
Bullimore et al.
The potential benefits of myopia control have been reported to outweigh the risks as it has been recently estimated that between 4 and 7 patients with a mean age of 12 years need to receive myopia control treatment with contact lenses to prevent 5 years of visual impairment (assuming a mean life expectancy of 82 years), while fewer than 1 in 38 will experience a loss of vision as a result of suffering from microbial keratitis due to myopia control contact lens wear.
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Orthokeratology
Pediatric Microbial Keratitis With Overnight Orthokeratology in Russia
Bullimore et al.
A recent study estimated the incidence of microbial keratitis in children wearing overnight orthokeratology lenses in Moscow, Russia. The number of children wearing orthokeratology lenses was estimated based on the review of over 1,300 patient records from 13 Doctors Lens clinics between 2010 and 2018. To identify cases of microbial keratitis, all episodes of infiltrative keratitis from Morozovskaya City Children's Clinical Hospital in 2018 were recorded and adjudicated by three experienced ophthalmologists. Incidence was calculated as the number of cases divided by the estimated number of wearers. Based on a 7% or 10% annual discontinuation rate, the estimated number of children wearing lenses in 2018 was 10,307 or 9,422, respectively. During 2018, 5 cases of microbial keratitis were found attributed to orthokeratology lens wear. The annual incidence of microbial keratitis associated with orthokeratology lens wear was estimated between 4.9 (95% confidence interval[CI]: 2.1-11.4) and 5.3 (95% CI: 2.3-12.4) per 10,000 patient years assuming a 7% or 10% discontinuation rate, respectively. Such estimated rates of microbial keratitis in children wearing overnight orthokeratology in Moscow is lower than a previous United States study and similar to rates associated with use of daily wear soft contact lenses.
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Lens Care
Factors Affecting Microbial Contamination on the Back Surface of Worn Soft Contact Lenses
Tan et al.
Microbial contamination of contact lenses has been associated with sight-threatening ocular complications. Proposed strategies to reduce lens contamination include improved hand hygiene before handling contact lenses and disposing of lenses after each wear to minimize potential effects of lens storage case contamination. A study investigated the effect of lens packaging type, chelating agent, and finger contamination on microbial contamination on the back surface of worn soft contact lenses. Twenty-five subjects completed each contralateral lens wear comparison in a randomized order: Smart Touch Technology versus conventional blister packaging for (1) silicone hydrogel lenses with ethylenediaminetetraacetic acid (EDTA) and (2) hydrogel lenses without EDTA in the packaging, and (3) silicone hydrogel lenses without EDTA versus hydrogel lenses with EDTA both in Smart Touch Technology packaging. Smart Touch Technology packaging was found effective in reducing the proportion of contaminated lenses. Although silicone hydrogel lenses were more likely to be contaminated, the presence of EDTA ameliorated this effect. Finger contamination was not associated with lens contamination. The results of this study highlight that Menicon’s Smart Touch Technology is effective in reducing contact lens contamination and thus it is likely to contribute to safer contact lens wear.
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Contact lenses for Keratokonus
Contact lenses are the primary form of visual correction for patients with keratoconus
Laura Downie and Richard Lindsay
Contact lenses are the primary form of visual correction for patients with keratoconus. Contemporary advances in contact lens designs and materials have significantly expanded the available fitting options for patients with corneal ectasia. Furthermore, imaging technology, such as corneal topography and anterior segment optical coherence tomography, can be applied to both gain insight into corneal microstructural changes and to guide contact lens fitting. A review paper from Downie and Lindsay
provides a comprehensive summarize of the range of contact lens modalities, including soft lenses, hybrid designs, rigid lenses, piggyback configurations, corneo-scleral, mini-scleral and scleral lenses currently available for the optical management of keratoconus.
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Myopia Control
The Scientific Bureau of World Society of Paediatric Ophthalmology and Strabismus recommends treatment options for myopia control
Seo Wei Leo
In a review paper, Seo Wei Leo from the Scientific Bureau of World Society of Paediatric Ophthalmology and Strabismus concluded that controlling the onset of myopia is now possible through increasing time outdoors whereas slowing the progression of myopia can be successfully achieved with interventions like atropine and orthokeratology.
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Compliance
Hand washing essential for safe and effective contact lens wear
Desmond Fonn and Lyndon Jones
Lack of or inadequate hand washing is a risk factor in the development of contact lens related microbial keratitis and corneal inflammatory events. There is compelling evidence that proper hand washing with soap can save lives, which it is now of outmost importance during the covid pandemic. Contact lens wearers are also guilty of poor hand washing behavior but there is scant evidence that education of hand washing procedures of lens wearers alters patient non-compliance. Adequate patient education with regards to hand hashing is critical for safe and effective contact lens wear
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Myopia Control
The International Myopia Institute has synthesed the research evidence to date on the most important and relevant aspects related to myopia, including recommended guidelines for myopia control
International Myopia Institute
With the growing prevalence of myopia, already at epidemic levels in some countries, there is an urgent need for new management approaches. However, with the increasing number of research publications on the topic of myopia control, there is also a clear necessity for agreement and guidance on key issues, including on how myopia should be defined and how interventions should be appropriately and ethically applied. The International Myopia Institute, with help from more than 85 multidisciplinary experts in the field, recently published seven critical reviews that syntheses the research evidence to date on the most important and relevant aspects related to myopia. These reports form the basis for recommended guidelines for eye care practitioners.
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Contact lenses for Children
The Safety of Soft Contact Lenses in Children
Mark A Bullimore
There is increasing interest in fitting children with soft contact lenses. A review collated data from a range of studies to estimate the incidence of complications, specifically corneal infiltrative events and microbial keratitis, in patients under the age of 18 years.
Nine prospective studies representing 1800 patient years of wear in 7- to 19-year-olds included safety outcomes. In three large prospective studies representing between 159 and 723 patient years of soft contact lens wear in patients 8 to 14 years, the incidence of corneal infiltrative events is up to 136 per 10,000 years. Data from a large retrospective study show similar rates of corneal infiltrative events: 97 per 10,000 years in 8- to 12-year-olds and 335 per 10,000 years in 13- to 17-year-olds. None of the prospective studies report any cases of microbial keratitis. One retrospective study found no cases of microbial keratitis occurred in 8- to 12-year-olds and an incidence of 15 per 10,000 patient years in 13- to 17-year-olds -no higher than the incidence of microbial keratitis in adults wearing soft contact lenses on an overnight basis. This review concluded that the incidence of corneal infiltrative events in children is no higher than in adults, and in the youngest age range of 8 to 11 years, it may be markedly lower.
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Myopia Management
Global trends in myopia management attitudes and strategies in clinical practice - 2019 Update
Wolffsohn et al.
A self-administrated, internet-based questionnaire was distributed in eight languages, through professional bodies to eye care practitioners globally. The questions examined: awareness of increasing myopia prevalence, perceived efficacy of available strategies and adoption levels of such strategies, and reasons for not adopting specific strategies. Over 1300 eye care practitioners from the 5 different continents responded to the questionnaire. Concern was highest in Asia and lowest in Australasia. Practitioners from Asia also considered their clinical practice of myopia control to be the most active, the North American practitioners being the least active. Orthokeratology was perceived to be the most effective method of myopia control, followed by pharmaceutical approaches and approved myopia control soft contact lenses. Most practitioners did not consider single-vision distance under-correction to be an effective strategy for attenuating myopia progression, but prescribed single vision spectacles or contact lenses as the primary mode of correction for myopic patients. The main justifications for their reluctance to prescribe alternatives to single vision refractive corrections were increased cost and inadequate information. While practitioner concern about myopia and the reported level of activity have increased in recent years, the vast majority of eye care clinicians still prescribe single vision interventions to young myopes.
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Compliance
Soft contact lens wearers' compliance during the COVID-19 pandemic
Vianya-Estopa et al.
An online survey distributed in the UK and Ireland explored contact lens wearers' compliance behaviors, attitudes and concerns during the COVID-19 pandemic. Two hundred and forty-seven responses were received (34.3 ± 11.7 years old, 79% female). Seventy nine percent of participants reported that they were self-isolating or rigorously following social distance advice. Fifty-six percent of participants reported using their lenses less during the pandemic. Eighty-seven percent of respondents reported following the recommended 20-second rule most times/every time and 96% used soap and water during handwashing. Eleven percent of respondents admitted not following recommendations regarding disposal of lenses and 18% would not consider ceasing lens wear if unwell (with flu/cold) during the pandemic. In summary, respondents reported wearing their contact lenses less than usual. In summary, although good compliance with handwashing was observed during the COVID-19 pandemic, soft reusable lens wearers showed a statistically significant lower compliance with lens wear and care compared to daily disposable lens wearers.
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Contact Lens Care
Subjective Comfort and Physiology with Modern Contact Lens Care Products
Berntsen et al
A study compared subjective comfort and ocular physiology with three multipurpose solutions (MPSs) to that of a peroxide-based system with three different soft contact lens materials in 236 habitual soft contact lens wearers. Subjects were randomly assigned to one of three lens types, including one hydrogel and two silicone hydrogel contact lenses. A new lens of the assigned type was worn for 10 to 14 days each while using one of four MPSs. After using each care solution, biomicroscopy was performed and subjective comfort and comfortable wear time (CWT) were assessed and compared to that of the peroxide solution. Comfort score across all lens types with each MPS was not significantly different than with the peroxide solution. There were no differences in CWT between each MPS and the peroxide solution for any lens. Six MPS/material combinations had no clinically meaningful change in corneal staining versus peroxide. Staining was < grade 1 for all combinations. In conclusion, comparable levels of comfort were found between the latest generation of MPSs compared to peroxide disinfection indicating that the current lens care systems investigated in this study are generally appropriate for use with the contact lenses tested.
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α Ortho-K
α Ortho-K Results of a Three-Year Clinical Trial on Treatment of Myopia in Children
CHANG Yong, XIE Pei-ying, WANG De-chen, CHI Hui, XHOU Jian-lan
Beijing Internet Eyecare Optometry & Ophthalmology Clinic
To evaluate the effect and safety of long-term wearing high precision ORTHO-K contact lens for myopic
children and adolescents.
Design
Retrospective case series.
Participants
150 myopic children and adolescents.
Methods
We examined 150 patients (300 eyes) who wore ORTHO-K lens for 3 years in Beijing Internet Eyecare Optometry & Ophthalmology Clinic. Following examinations had been performed for baseline and all annual follow-up visits: slit lamp exam, uncorrected visual acuity (UCVA), and tear secretion, eye axial length, corneal thickness, corneal endothelial cell density, percentage of hexagon and corneal curvature values. We also selected 66 eyes switching to ORTHO-K from other brands for evaluation of comfort, clarity and cleanliness.
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COVID-19
The COVID-19 pandemic: Important considerations for contact lens practitioners
Lyndon Jones et al
A novel coronavirus (CoV), the Severe Acute Respiratory Syndrome Coronavirus - 2 (SARS-CoV-2), results in the coronavirus disease 2019 (COVID-19). As information concerning the COVID-19 disease continues to evolve, patients look to their eye care practitioners for accurate eye health guidance. There is currently no evidence to suggest an increased risk of contracting COVID-19 through contact lens (CL) wear compared to spectacle lens wear and no scientific evidence that wearing standard prescription spectacles provides protection against COVID-19 or other viral transmissions.
https://www.contactlensjournal.com/article/S1367-0484(20)30055-2/fulltext
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COVID-19
Could telehealth help eye care practitioners adapt contact lens services during the COVID-19 pandemic?
Manbir Nagra et al
The COVID-19 pandemic has necessitated government-imposed restrictions on social interactions and travel. For many, the guidance has led to new ways of working, most notably a shift towards working remotely. While eye care practitioners (ECPs) may continue to provide urgent or emergency eye care, in many cases the travel restrictions present a unique challenge by preventing conventional face-to-face examination. Telephone triage provides a useful starting point for establishing at-risk and emergency patients. Approaches to teleoptometry in contact lens practice primarily includes smartphone based ocular imaging and assessment of visual acuity. However, the absence of a comprehensive evidence base for teleoptometry limits ECPs, particularly during a pandemic. Advances in the field, such as ocular self-imaging, could help move this field forwards.
https://www.contactlensjournal.com/article/S1367-0484(20)30075-8/fulltext
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Care solution
Antimicrobial properties of new rigid gas-permeable contact lens multipurpose solution formulated with polylysine as disinfecting agent
Osamu Mori and Megumi Toyohara
A study presented at a recent conference of the British Contact Lens Association compared the antimicrobial properties of a new rigid gas-permeable (RGP) contact lens multipurpose solution (MPS) formulated with Polylysine as disinfecting agent against other commercially available MPS formulated with other disinfecting agents. Four commercially available RGP-MPS were compared according to ISO14729 stand-alone disinfection test: MPS-A (polylysine), MPS-B (PHMB + chlorhexidine), MPS-C (PHMB), MPS-D (Oxychlorite + hydrogen peroxide) and MPS-E (Polyquad). Antimicrobial properties were assessed with/without artificial tear as organic load for time (5–360 min) and temperature-dependence (10–32 ºC). MPS-A, MPS-B and MPS-E showed sufficient efficacy under all test conditions. MPS-C showed insufficient efficacy against fungi and decreased efficacy at low temperature and with organic load. MPS-D barely showed efficacy against all microorganisms tested. The new RGP-MPS formulated with Polylysine represents a safe and effective care solution for use with rigid gas-permeable contact lenses.
https://www.sciencedirect.com/science/article/pii/S1367048414001453
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Myopia control
Overnight orthokeratology
Mark A Bullimore and Leah A. Johnson
A recent publication in the Contact Lens & Anterior Eye provided an interesting review of the current status of the use of overnight orthokeratology contact lenses. Overnight orthokeratology lenses are currently approved in countries all over the world for the temporary reduction in myopia, and recently, one lens design has received regulatory approval for myopia control in Europe. The modern orthokeratology lens has a substantial history from its origins of attempting to flatten the corneal curvature with a spherical rigid contact lens to sophisticated gas permeable lenses, designed to reshape the cornea. Currently, these lenses are predominantly prescribed for children to slow myopia progression and limit axial elongation of the eye. The article reviews the peer-reviewed literature on the efficacy of orthokeratology for myopia control, sustainability after treatment is discontinued, and the safety concerns of overnight contact lens wear.
https://www.contactlensjournal.com/article/S1367-0484(20)30061-8/fulltext
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Myopia control
Short-term and long-term changes in corneal power are not correlated with axial elongation of the eye induced by orthokeratology in children
Jacinto Santodomingo-Rubido et al
In this study, it was assessed the relationship between short-term and long-term changes in power at different corneal locations relative to the change in central corneal power and the 2-year change in axial elongation relative to baseline in white European children wearing orthokeratology contact lenses (Ortho-K).
The result showed the reduction in central corneal power and relative increase in paracentral and pericentral power induced by OK over 2 years were not significantly correlated with concurrent changes in axial length of white European children.
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Myopia control
Short- and Long-Term Changes in Corneal Aberrations and Axial Length Induced by Orthokeratology in Children Are Not Correlated
Jacinto Santodomingo-Rubido et al.
The study was conducted to assess the correlation between changes in corneal aberrations and the 2-year change in axial length in children fitted with orthokeratology contact lenses (ortho-K).
It was found short-term and long-term ortho-K lens wear induces significant changes in corneal aberrations that are not significantly correlated with changes in axial elongation after 2-years.
https://insights.ovid.com/crossref?an=00140068-201711000-00005
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Myopia control
Long-term Efficacy of Orthokeratology Contact Lens Wear in Controlling the Progression of Childhood Myopia
Jacinto Santodomingo-Rubido, César Villa-Collar, Bernard Gilmartin, Ramón, Gutiérrez-Ortega & Keiji Sugimoto
The study was conducted over 7 years to compare the axial length growth of white European myopic children from 6 to12 years old wearing orthokeratology contact lenses (ortho-K) to a control group over a 7-year period. The axial length growth of ortho-K group was 33% slower than the on
https://www.tandfonline.com/doi/full/10.1080/02713683.2016.1221979?scroll=top&needAccess=true
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Myopia control
The effects of entrance pupil centration and coma aberrations on myopic progression following orthokeratology
Jacinto Santodomingo Rubido et al.
The study was conducted in Spain to assess the potential association between entrance pupil location relative to the coaxially sighted corneal light reflex (CSCLR) and the progression of myopia in children fitted with orthokeratology (OK) and to investigate whether coma aberration induced by decentration of the entrance pupil centre relative to the CSCLR, as well as following OK treatment, is correlated with the progression of myopia. A significant increase in vertical coma was found with OK lens wear compared to baseline (p < 0.001) but total root mean square (RMS) coma was not associated with the change in axial length (all p > 0.05). Entrance pupil location relative to the CSCLR was not significantly affected by either OK lens wear or an increase in axial length. Greater magnitude coma aberrations found at the entrance pupil centre in comparison to the CSCLR might be attributed to centration of orthokeratological treatments at the CSCLR.
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Myopia control
Effect of low-addition soft contact lenses with decentered optical design on myopia progression in children: a pilot study
Takashi Fujikado et al.
The pilot study was conducted to evaluate the effect of decentered optical design low-addition soft contact lenses for controlling myopia progression over 2 years. Control group wore monofocal soft contact lenses. As a result of this study, it was observed that the decentered optical design low-addition soft contact lenses was effective to suppress the axial elongation compared to control group, however, we did not find significant difference on refractive error.
The reduction of the progression of myopia by low-addition soft CLs warrants further investigations.
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Myopia control
Factors Preventing Myopia Progression With Orthokeratology Correction
Jacinto Santodomingo-Rubido et al
The study was conducted in Spain to examine which baseline measurements constitute predictive factors for axial length growth over 2 years in children wearing orthokeratology contact lenses (ortho-k) and single-vision spectacles (SV). Orthokeratology is a successful treatment option in controlling axial elongation compared to SV in children of older age, had earlier onset of myopia, were female, had lower rate of myopia progression before baseline, had lower myopia at baseline, had longer anterior chamber depth, had greater corneal power, had more prolate corneal shape, had larger iris and pupil diameters, and had lower levels of parental myopia.
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Myopia control
Myopia Control with Orthokeratology Contact Lenses in Spain (MCOS): Refractive and Biometric Changes
Jacinto Santodomingo-Rubido et al
The study was conducted for 2 years in Spain, for the purpose of comparing axial length growth between white children with myopia wearing orthokeratology contact lenses (ortho-k) and distance single-vision spectacles (SV). The axial length growth was observed with both groups, however, that of SV group was significantly greater than ortho-k group. This result showed the ortho-k lowered the axial length growth and might be effective to control the myopia progression.
Open Access https://iovs.arvojournals.org/article.aspx?articleid=2168338
https://iovs.arvojournals.org/article.aspx?articleid=2168338
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Myopia control
Retardation of Myopia in Orthokeratology (ROMIO) Study: A 2-Year Randomized Clinical Trial
Pauline Cho; Sin-Wan Cheung
The study was conducted for 2 years in Hong Kong, for the purpose to evaluate the effectiveness of orthokeratology contact lenses (ortho-k), which is thought to be one of the means for the myopia progression control. One group was assigned to wear ortho-k, and the other to wear single-vision glasses as a control. As a result of measuring the axial length, the axial length elongation of ortho-k group was 43% slower than of the control group, so that the ortho-k might be effective to control the myopia progression.
https://iovs.arvojournals.org/article.aspx?articleid=2127470
